The Committees backed the inclusion of abuse-deterrent labelling for intranasal (11 to four) and intravenous (nine to six) routes of abuse, but not for the oral route (six to nine).

The misuse of prescription opioids remains a serious and persistent issue in the US. According to the American Society of Addiction Medicine, 1.9 million people in the country had a substance use disorder involving prescription pain relievers in 2014, while four in five new heroin users started out misusing prescription painkillers, highlighting the scope of the problem.

Pfizer is hoping that its drug will help to address this, as ALO-02 uses technology which should discourage tampering associated with prescription opioid misuse and abuse. It consists of extended-release oxycodone pellets that surround a sequestered core of naltrexone; when the pellets are crushed, the naltrexone is released to counteract the effects of oxycodone.

Data from a Phase III trial in 2012 showed that Pfizer's drug is as safe as other opioids on the market, the most common side effects being headache, nausea, vomiting and constipation.

The FDA does not have to follow the advice of its advisory panels, but generally tends to do so.